Diversity of boreal small species of Cortinarius subgenus Telamonia with Salix

Abstract

This work presents the genetic and morphological diversity of small <em>Cortinarius</em> subgenus <em>Telamonia</em> species found from moist <em>Salix</em> thickets in Finland. The boreal fungi were compared with several type and other specimens from the alpine zone or similar habitats from the temperate zone. The boreal and alpine zones had many common species: nearly all boreal species grew in the alpine zone with dwarf <em>Salix</em>. The species often had wide distributions, extending to North America. The genetic analyses consisted of ITS and RPB2 sequences. Both genetic and morphological variation was high. The species formed complexes, where the boundaries among species were often obscure. Very close sibling species were delimited based on differences at the same sites. Twenty-three boreal species were recognized. Four of them are described here as new: <em>C. paulus</em> and <em>C. paululus</em> as sibling species to <em>C. pauperculus</em> J.Favre, <em>C. rusticelloides</em> as a sibling species to <em>C. rusticellus</em> J.Favre, and <em>C. vienoi</em> as a sibling species to <em>C. perzonatus</em> Reumaux. <em>Cortinarius sagarum</em>, a sibling species to <em>C. comatus</em> J.Favre and <em>C. vulpicolor</em> M.M.Moser & McKnight, is described as new from arctic-alpine zones.

New Insights into Alpine Cortinariaceae (Basidiomycota): Three New Species, Two Type Revisions, and a New Record for the Alpine Zone

“…The DNA-based revisions of Telamonia simultaneously published by Liimatainen et al [ 2 ] and, specifically focusing on alpine taxa, by Kokkonen [ 14 ], have clearly highlighted the need to revise the entire traditionally accepted taxonomy for these small fungi. The sequencing of the type collections was a key step for this ambitious challenge.…”

“…The sequencing of the type collections was a key step for this ambitious challenge. Liimatainen et al [ 2 ] published 11 ITS type sequences from Favre’s alpine species of Telamonia , and Kokkonen [ 14 ] published 6 more from Favre’s species and 3 from Lamoure’s taxa. While most species have thus been elucidated (unlocking the identification of many arctic–alpine collections and environmental samplings), those which could not be sequenced for various reasons remain enigmatic.…”

“…A series of prospections in the Vanoise region (Savoie, France) close to Kühner and Lamoure’s areas by F. A. and P.-A. M. between 2010 and 2019, and privileged access to D. Lamoure’s herbarium (LY) in 2020, yielded important alpine material that could be sequenced and compared to the data already published [ 2 , 14 ]. Most of the collections could be attributed to taxa already reported from Vanoise [ 6 ] and confirmed here, but some of them were of special interest and are the object of the present article.…”

<strong><em>Cortinarius jiaoheensis</em> (Cortinariaceae), a new species of <em>Cortinarius</em> subgenus <em>Telamonia</em> section <em>Flexipedes</em>, from northeast China</strong>

“…subgenus Telamonia (Fr.) Trog (1844: 43), the most diverse and taxonomically challenging subgenus in Cortinarius, has most of its species occurring in the Northern Hemisphere (Niskanen 2007;Niskanen et al 2008;Dima et al 2014;Soop et al 2019;Kokkonen et al 2020), and some in the Southern Hemisphere (Peintner et al 2003;Garnica et al 2005). Telamonioid species are characterized by a dry stipe and dry or fairly dry, and in most species, ±hygrophanous pileus.…”

Fungal Planet description sheets: 1478–1549

“…However, this might also result from the recent diversification of the lineage, which would not have allowed enough time for mutations to accumulate and polymorphisms to be fixed (incomplete lineage sorting) at the ITS locus of genetically isolated species to unambiguously distinguish them. We tend to favour the latter hypothesis because some species complexes not resolved in ITS phylogenies, are deciphered by the use of the RPB2 phylogenetic marker ( Kokkonen 2020 ). It seems thus that in sect.…”